I have 71 scamp with a junk yard 12k mile magnum 360. Im looking at doing some mods over the winter. Right now the motor is a stock long block coverted to a carb. I will list what Ive done and what I plan on doing below. Let me know what you think.

71 Scamp
Magnum 360
add LA style timing cover and water pump
Air Gap intake with a 650 speed demon mech secondards
1-5/8" headers with 3" exhaust Flowmaster with turndowns before the axles
reverse manual valve body 904
PTC 9.5" converter
4.30 SureGrip
235-60R15 MT drag radials
1/2" braided fuel system with elec pump and cell in tank
The car weight is about 3400 with driver. I made a couple of passes with this set up and went 13.8 at 94mph. I ran out of motor at about 1000ft.

Here is what I want to do.
I spoke with Ryan J at Shady Dell about a stage one port job on my stock heads, and set them up for spring that can handle more lift. As well as a 5 angle valve job.

I also have spoken with Hughes Engines about a cam. They recommend the 222/228 at .050 and .520/.544. I cant remeber the centerline. I think 108, but could be wrong.

Im not looking for to crazy a set up. I like to drive my car on the street. Also do you think the 4.30's are to much for my setup? Would 3.55's work better? Thats all I can think of for know.

Thanks, Bill

You need more motor and carb for those gears, cam and heads are a good place to start

I'd think your overgeared for the combo. Very wimpy stock valve springs and girly cam are first to go. I ran a stock junkyard 360 magnum in a Dakota(3600lb?) years ago,ran 14.00 @98mph with 3.55 gears and stock converter,500 auto/od tranny. Try a taller tire and upgrade the cam/valve springs and you should pick up.

I had a 360 magnum 380 horse engine in my 72 Dart.I had 3.91 gears with a mild converter in it.I ran it one time and ran 13.07 @ 107.89 mph.I had planned to up my shift point each run to see how it ran,but i only got the one run.5500 rpm was where i started at which was way to low.I'm sure another run would have put me in the 12's.235/60 Firestone Firehawk tires and 2980# car weight.

Hey Bill I'll make it easy for you,just buy my 360 magnum stocker motor for $3500 and run low 12's at will with your current gear and converter!! Hell..,I ran 4.89 gears on the street for 10 yrs with no problem. I used to DRIVE 3 hrs to Norwalk,Oh. with a similiar set-up. Of course I was young and fearless back then!!
Terry

I like this one, it may be soft under 3k but with a 9.5" converter/4.30's and 26" tires you're never in that range anyways, It should turn 66-6700 out the back which would be about 113-114mph. It will need good springs and adjustable rockers to set lifter preload, the lift is approx .580/.577 if you run the stock 1.6 ratio.


Brand COMP Cams
Manufacturer's Part Number 20-813-9
Part Type Camshafts
Product Line COMP Cams Xtreme Energy Retro-Fit Camshafts
Summit Racing Part Number CCA-20-813-9

Cam Style Hydraulic roller tappet
Basic Operating RPM Range 2,500-6,200
Intake Duration at 050 inch Lift 236
Exhaust Duration at 050 inch Lift 242
Duration at 050 inch Lift 236 int./242 exh.
Advertised Intake Duration 286
Advertised Exhaust Duration 294
Advertised Duration 286 int./294 exh.
Intake Valve Lift with Factory Rocker Arm Ratio 0.544 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.541 in.
Valve Lift with Factory Rocker Arm Ratio 0.544 int./0.541 exh. lift
Lobe Separation (degrees) 110
Intake Valve Lash 0.000 in.
Exhaust Valve Lash 0.000 in.
Computer-Controlled Compatible No
Grind Number XR286HR-10
Quantity Sold individually.

Since you have the airgap and a 650 carb I would say 3.91 would be ideal. Maybe even 3.73's would be better if that tire is 26" tall.

But with changes to the cam and heads I might leave the gear alone for now. Especially if you don't mind it and if it happens to dead hook at the track. You might try going to a taller tire after these wear out, (if it will fit) if you are inclined to gear it taller after the changes.

If you keep that gear I might try a Mopar M-1 open plenum manifold and a 750.

The 4.30's don't bother me. I just want what will work best for my set up. Im also limited on the size tire I can run. The 235-60r15 is as tall as it gets. I do drive the car on the street more then I race it.